Odd to Use "West Bank"

As we know, the names of the geographical area which Israel administers since 1967 that were within the original territory of the Mandate for Palestine are Judea and Samaria.
The term "West Bank" was first used in April 1950 when Jordan illegally annexed that region.
However, in seeking to quote a section from the 1949 Jordan-Israel Armistice Agreement, I found that Israel's Ministry for Foreign Affairs, in its introduction to that material, used the term "West Bank" in describing the area.
Why is that?
The immediate international document relating to the geography of the area, the UN's 1947 Partition recommendation, used "Judea and Samaria" and not at all the "West Bank".
I hope the acting Minister, Benjamin Netanyahu and his deputy, Tzipi Hotovely, see this post and respond.
And correct it.